Jealousy is an emotional response that typically arises when a person perceives a threat to a valued relationship or possession. It often involves feelings of insecurity, fear, concern, and resentment. Jealousy can be experienced in various types of relationships, such as romantic, familial, or platonic, and it can stem from real or imagined threats. It's a complex emotion that can have both negative and positive aspects, motivating individuals to strengthen relationships or leading to destructive behaviors if not managed properly.